[saudisinaudis]

Does anyone have an ample comparison based on the metrics mentioned in the title when it comes to Midpipe only VS Downpipe only systems?
I’m not sold into full exhaust systems as they are usually far louder than preference, and I’ve heard a midpipe coldstart live that sounded like a stuck chainsaw. It was very unpleasant to hear.
Does anyone have videos / experiences who could chime in?

[forcefed]

Originally Posted by saudisinaudis

I’ve heard a midpipe coldstart live that sounded like a stuck chainsaw. It was very unpleasant to hear.

Was that a single midpipe or I guess double midpipe? My single midpipe sounds almost stock, a bit louder but nothing like you describe.

There's a potential fix for resonance issues, wrap the exhaust with header wrap, look into that if you want to get rid of rasp/trumpet sounds. The thickness of the pipe causes these issues, seems most of our exhausts are just too thin walled.

[saudisinaudis]

Originally Posted by forcefed

Was that a single midpipe or I guess double midpipe? My single midpipe sounds almost stock, a bit louder but nothing like you describe.

Maybe double, I don’t know. I just knew that I wanted my M3 to sound nothing like that.
I believe he deleted all resonators behind the cat, leaving only downpipes and the muffler.

[mike@x-ph.com]

The downpipes will provide more sound than the midpipe; it will amplify the existing sound of the car and make everything louder

The midpipe will increase the sound, but depending on which midpipe you choose, it will also change the car's sound and provide a deeper and cleaner tone.

Aside from the CEL that is a concern with downpipes, I recommend you start with a single midpipe, as you need to clean the sound of your exhaust before worrying about making it louder.

[saudisinaudis]

Originally Posted by mike@x-ph.com

The downpipes will provide more sound than the midpipe; it will amplify the existing sound of the car and make everything louder

The midpipe will increase the sound, but depending on which midpipe you choose, it will also change the car's sound and provide a deeper and cleaner tone.

Aside from the CEL that is a concern with downpipes, I recommend you start with a single midpipe, as you need to clean the sound of your exhaust before worrying about making it louder.

Concerned with the cutting and welding required for midpipes and the potential difficulty of bringing it back if I find its combination with the downpipe overly loud. My idea is that midpipes dont provide as much volume increase as I need, downpipe + midpipe provide too much loudness, and downpipe only strikes the perfect balance. I like the stock tone, but I fear that I’ll change my mind once its amplfiied

[Info@mad-us.com]

Neither sound bad in my option. The single doesn't tend to valve rattle like some others

Catless cold start with stock exhaust -

Cold start single midpipe with and without valve controller vs stock-

Single resonated midpipe cold start

[mike@x-ph.com]

Originally Posted by saudisinaudis

Concerned with the cutting and welding required for midpipes and the potential difficulty of bringing it back if I find its combination with the downpipe overly loud. My idea is that midpipes dont provide as much volume increase as I need, downpipe + midpipe provide too much loudness, and downpipe only strikes the perfect balance. I like the stock tone, but I fear that I’ll change my mind once its amplfiied

it sounds like you like the downpipes sound the best, if thats the case, i recommend you start with the downpipes.

[Massg80]

Do downpipes vioid any of the warranty? Sorry I’m a newbie, also if you add an exhaust to the downpipe make a big difference?

[Info@mad-us.com]

Originally Posted by Massg80

Do downpipes vioid any of the warranty? Sorry I’m a newbie, also if you add an exhaust to the downpipe make a big difference?

They can not technically void any warranty unless they can prove it caused the issue however the dealer can choose not to work on your vehicle do to emissions issues. In most cases if this were to happen they would request you to return the downpipes back to factory spec.

If this is a large issue for you I suggest sticking with simple mods such as a midpipe and valve controller.

[mike@x-ph.com]

Originally Posted by Massg80

Do downpipes vioid any of the warranty? Sorry I’m a newbie, also if you add an exhaust to the downpipe make a big difference?

the downpipes will not void your warranty as they do not add any extra stress to stock components, if anything they reduce the backpressure on your turbos.